The effect of methylene blue treatment on aspiration pneumonia

BACKGROUND

The study aimed to examine whether methylene blue (MB) prevents different pulmonary aspiration materials-induced lung injury in rats.

METHODS

The experiments were designed in 60 Sprague-Dawley rats, ranging in weight from 250-300 g, randomly allotted into one of six groups (n = 10): saline control, Biosorb Energy Plus (BIO), hydrochloric acid (HCl), saline + MB treated, BIO + MB treated, and HCl + MB treated. Saline, BIO, and HCl were injected into the lungs in a volume of 2 mL/kg. After surgical procedure, MB was administered intraperitoneally for 7 days at a daily dose of 2 mg/kg per day. Seven days later, rats were killed, and both lungs in all groups were examined biochemically and histopathologically.

RESULTS

Our findings show that MB inhibits the inflammatory response reducing significantly (P < 0.05) peribronchial inflammatory cell infiltration, alveolar septal infiltration, alveolar edema, alveolar exudate, alveolar histiocytes, interstitial fibrosis, granuloma, and necrosis formation in different pulmonary aspiration models. Pulmonary aspiration significantly increased the tissue hydroxyproline content, malondialdehyde levels, and decreased (P < 0.05) the antioxidant enzyme (superoxide dismutase and glutathione peroxidase) activities. MB treatment significantly (P < 0.05) decreased the elevated tissue hydroxyproline content and malondialdehyde levels and prevented the inhibition of superoxide dismutase and glutathione peroxidase (P < 0.05) enzymes in the tissues. Furthermore, there is a significant reduction in the activity of inducible nitric oxide synthase (iNOS), terminal deoxynucleotidyl transferase dUTP nick end labeling, and arise in the expression of surfactant protein D in lung tissue of different pulmonary aspiration models with MB therapy.

CONCLUSIONS

MB treatment might be beneficial in lung injury and therefore shows potential for clinical use.

The effect of hyperbaric oxygen treatment on aspiration pneumonia

We have studied whether hyperbaric oxygen (HBO) prevents different pulmonary aspiration materials-induced lung injury in rats. The experiments were designed in 60 Sprague-Dawley rats, ranging in weight from 250 to 300 g, randomly allotted into one of six groups (n = 10): saline control, Biosorb Energy Plus (BIO), hydrochloric acid (HCl), saline + HBO treated, BIO + HBO treated, and HCl + HBO treated. Saline, BIO, HCl were injected into the lungs in a volume of 2 ml/kg. A total of seven HBO sessions were performed at 2,4 atm 100% oxygen for 90 min at 6-h intervals. Seven days later, rats were sacrificed, and both lungs in all groups were examined biochemically and histopathologically. Our findings show that HBO inhibits the inflammatory response reducing significantly (P < 0.05) peribronchial inflammatory cell infiltration, alveolar septal infiltration, alveolar edema, alveolar exudate, alveolar histiocytes, interstitial fibrosis, granuloma, and necrosis formation in different pulmonary aspiration models. Pulmonar aspiration significantly increased the tissue HP content, malondialdehyde (MDA) levels and decreased (P < 0.05) the antioxidant enzyme (SOD, GSH-Px) activities. HBO treatment significantly (P < 0.05) decreased the elevated tissue HP content, and MDA levels and prevented inhibition of SOD, and GSH-Px (P < 0.05) enzymes in the tissues. Furthermore, there is a significant reduction in the activity of inducible nitric oxide synthase, TUNEL and arise in the expression of surfactant protein D in lung tissue of different pulmonary aspiration models with HBO therapy. It was concluded that HBO treatment might be beneficial in lung injury, therefore, shows potential for clinical use.

Preventive effects of curcumin on different aspiration material-induced lung injury in rats

PURPOSE

We have studied whether curcumin protects different pulmonary aspiration material-induced lung injury in rats.

MATERIALS AND METHODS

The experiments were designed in 60 Sprague-Dawley rats, randomly allotted into one of six groups (n=10): normal saline (NS, control), enteral formula (Biosorb Energy Plus, BIO), hydrochloric acid (HCl), NS+curcumin-treated, BIO+curcumin-treated, and HCl+curcumin-treated. NS, BIO, HCl were injected in to the lungs. The rats received curcumin twice daily only for 7 days. Seven days later, both lungs in all groups were examined histopathologically, immunohistochemically, and biochemically. Histopathologic examination was performed according to the presence of peribronchial inflammatory cell infiltration, alveolar septal infiltration, alveolar edema, alveolar exudate, alveolar histiocytes, interstitial fibrosis, granuloma, and necrosis formation. Immunohistochemical assessments were examined for the activity of inducible nitric oxide synthase (iNOS) and the expression of surfactant protein D (SP-D). Malondialdehyde (MDA), hydroxyproline (HP), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activity were measured in the lung tissue.

RESULTS

Our findings show that curcumin inhibits the inflammatory response reducing significantly (P<0.05) all histopathological parameters in different pulmonary aspiration models. Pulmonary aspiration significantly increased the tissue HP content, MDA levels and decreased the antioxidant enzyme (SOD, GSH-Px) activities. Curcumin treatment significantly decreased the elevated tissue HP content, and MDA levels and prevented inhibition of SOD, and GSH-Px enzymes in the tissues. Furthermore, our data suggest that there is a significant reduction in the activity of iNOS and a rise in the expression of SP-D in lung tissue of different pulmonary aspiration models with curcumin therapy.

CONCLUSION

Our findings support the use of curcumin as a potential therapeutic agent in acute lung injury.